Then by accident I found the rtl-sdr software radio project. Long story short is that a $20 USB dongle designed for receiving digital TV can also be used as a wideband receiver from 64Mhz to over 1.6GHz. Yes it works on Linux too.

Hey guys, I'm John (the guy from the video). We are very excited to have made it here on Slashdot! We just wanted to post up a comment that we also left on the Kickstarter page addressing the concerns of those interested in frequencies under 300mhz. The usable frequency range of the bladeRF does indeed start at 300MHz but goes up to 3.8GHz. Having one (or even two) front-ends spanning this many octaves is a challenge, however the bladeRF performs exceptionally well over the entire range. That however may not have been the case had we included the circuitry needed to reach those lower frequencies. As a solution, we added an expansion board interface to the bladeRF. One of our first expansion boards will be a block up/down converter. We wanted to wait a little bit to get some feedback from people to see what frequency ranges people were interested in seeing. As of now it seems very likely that we will look at going from as close to DC as possible up to a minimum of 11GHz. So as soon as we do our engineering homework and see what's possible we will make an official announcement about this on the Kickstarter page.